Variable pneumatic sear for paintball gun

ABSTRACT

An improved paintball gun uses a low-pressure pneumatic sear to hold the firing valve closed against the high pressure gas occupying the other side of the valve. In this manner, only one operation is required between depressing the trigger and the firing of the paintball gun because a double-acting cylinder is not required as an interface between the trigger depression and actuation of the valve. The paintball gun is also substantially faster than existing electro-pneumatic paintball guns because it uses a blow forward bolt, in which higher-pressure gas is held directly behind the bolt and has only one direction to travel during the firing of the paintball gun.

CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit of U.S. Provisional Nos. 60/588,912and 60/654,262 filed Jul. 16, 2004 and Feb. 18, 2005 respectively, whichare incorporated by reference as if fully set forth.

FIELD OF INVENTION

The field of invention is the sport of paintball, and in particularpaintball markers used therein.

BACKGROUND

This invention relates generally to the construction of compressed gasguns and more particularly to the guns designed to propel a liquidcontaining frangible projectile, otherwise known as a “paintball”. Asused herein, the term “compressed gas” refers to any mean known in theart for providing a fluid for firing a projectile from a compressed gasgun, such as a CO2 tank, a nitrous tank, or any other means supplyinggas under pressure. Older existing compressed gas guns generally use amechanical sear interface to link the trigger mechanism to the hammer orfiring pin mechanism. In these guns, a trigger pull depresses the searmechanism which allows the hammer, under spring or pneumatic pressure,to be driven forward and actuate a valve that releases compressed gasthrough a port in the bolt, which propels a projectile from the barrel.

This design, however, has many problems, including increasedmaintenance, damage after repeated cycles, and a higher amount of forceis required to drive the hammer mechanism backwards to be seated on thesear. Also, because the sear and resulting hammer must be made ofextremely hard materials, the gun is heavy. Such weight is adisadvantage in paintball, where a player's agility works to hisadvantage.

To overcome the problems of a mechanical sear, people developed othersolutions. One solution uses a pneumatic cylinder, which uses spring orpneumatic pressure on alternating sides of a piston to first hold ahammer in the rearward position and then drive it forward to actuate avalve holding the compressed gas that is used to fire the projectile.Although the use of a pneumatic cylinder has its advantages, it requiresthe use of a stacked bore, where the pneumatic cylinder in the lowerbore and is linked to the bolt in the upper bore through a mechanicallinkage. It also requires increased gas use, as an independent pneumaticcircuit must be used to move the piston backwards and forwards. Afurther disadvantage is that adjusting this pneumatic circuit can bedifficult, because the same pressure of gas is used on both sides of thepiston and there is no compensation for adjusting the amount of recockgas, used to drive it backwards, and the amount of velocity gas, whichis the amount of force used to drive it forward and strike the valve.This results in erratic velocities, inconsistencies, and shoot-down. Inaddition, this technology often results in slower cycling times, asthree independent operations must take place. First, the piston must becocked. Second, the piston must be driven forward. Third, a valve isopened to allow compressed gas to enter a port in the bolt and fire aprojectile. Clearly, the above design leaves room for improvement.

Single-bore designs have also been developed which place the cylinderand piston assembly in the top bore, usually behind the bolt. Thisreduces the height of the compressed gas gun, but still requires that aseparate circuit of gas be used to drive the piston in alternatingdirections, which then actuates a valve to release compressed gas, whichdrives the bolt forward to launch a paintball. These are generally knownas spool valve designs. See, for instance, U.S. Pat. Nos. 6,644,295,5,613,483 and 5,494,024.

Existing spool valve designs have drawbacks as well. Coordinating themovements of the two separate pistons to work in conjunction with oneanother requires very precise gas pressures, port orifices, and timingin order to make the gun fire a projectile. In the rugged conditions ofcompressed gas gun use, these precise parameters are often not possible.In addition, adjusting the velocity of a compressed gas gun becomes verydifficult, because varying the gas pressure that launches a paintball inturn varies the pressure in the pneumatic cylinder, which causes erraticcycling.

What is needed is a compressed gas gun design that eliminates the needfor a separate cylinder and piston assembly and uses a pneumatic searinstead of a pneumatic double-acting cylinder to hold the firingmechanism in place prior to firing a projectile. This allows the gun tobe very lightweight and compact, and simplifies adjusting the recock gasused to cock the bolt and the gas used to fire the projectile.

SUMMARY

One aspect of the present invention provides an improved paintball gunthat uses a low-pressure pneumatic sear to hold the firing valve closedagainst the high pressure gas occupying the other side of the valve. Inthis manner, only one operation is required between depressing thetrigger and the firing of the paintball gun because a double-actingcylinder is not required as an interface between the trigger depressionand actuation of the valve. The improved paintball gun is alsosubstantially faster than existing electro-pneumatic paintball gunsbecause it uses a blow forward bolt, in which higher-pressure gas isheld directly behind the bolt and has only one direction to travelduring the firing of the paintball gun.

In operation, a preferably normally open electro-pneumatic valve directslow pressure compressed gas to the front of the firing valve, which isconnected to the bolt, which drives the valve backwards in a closedposition. On the rearward side of the firing valve, higher-pressure gasis occupying the space surrounding the surface of the firing valve. Whenthe trigger is depressed, it sends an electrical signal to theelectropneumatic valve that actuates it. When actuated, theelectro-pneumatic valve shuts off and vents to atmosphere the flow oflow-pressure gas to the front of the firing valve. As this low pressuregas is being vented, the higher pressure gas on the rear of the firingvalve overcomes the pressure on the front of the valve, and the firingvalve moves forward, allowing the higher pressure gas to escape aroundthe edges of the valve to be directed down through the center of thebolt to launch the projectile. When the electropneumatic valve isde-actuated, low-pressure gas is then directed to the front of thefiring valve, driving it rearwards to seat the valve.

BRIEF DESCRIPTION OF THE DRAWING(S)

Other objects of the invention will be more readily apparent uponreading the following description of embodiments of the invention andupon reference to the accompanying drawings wherein:

FIG. 1 is a side view of a compressed gas gun utilizing a variablepneumatic sear in the firing position.

FIG. 2 is a side view of a compressed gas gun utilizing a variablepneumatic sear in the loading position.

FIG. 3 is an expanded view of the variable pneumatic sear in the loadingposition.

FIG. 4 is an expanded view of the variable pneumatic sear in thelaunching position.

FIG. 5 is an expanded isometric view of the switches located within therecess.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

FIGS. 1-5 illustrate of a compressed gas gun incorporating a pneumaticsear. Referring to FIGS. 1 and 2, a paintball gun generally comprises amain body 3, a grip portion 45, a trigger 24, a feed tube 6, and abarrel 10. These components are generally constructed out of metal or asuitable substance that provides the desired rigidity of thesecomponents. Main body 3 generally is connected to a supply ofprojectiles by feed tube 6 as understood by those skilled in the art.Main body 3 is also connected to grip portion 45, which houses thetrigger 24, battery 64 and circuit board 63. The trigger 24 is operatedby manual depression, which actuates micro-switch 86 directly behindtrigger 24 to send an electrical signal to circuit board 63 to initiatethe launching sequence. Barrel 10 is also connected to body 3,preferably directly in front of feed tube 6, to allow a projectile to befired from the gun.

Hereinafter, the term forward shall indicate being towards the directionof the barrel 10 and rearward shall indicate the direction away from thebarrel 10 and towards the rear of main body 3. Preferably forward of thegrip portion 45, and also attached to main body 3, the regulator mount 2houses both the low-pressure regulator 21 and the high-pressureregulator 50. Compressed gas is fed from preferably a compressed gastank into the input port 49 on high-pressure regulator 50 to be directedto tube 7 to launch a projectile and to be directed to low pressureregulator 21 to cock the bolt tip 38 for loading. Both regulators 21, 50are constructed from principles generally known to those skilled in theart, and have adjustable means for regulating compressed gas pressure.

Referring more particularly to FIGS. 3 and 4, housed within main body 3is the firing mechanism of the gun. Firing mechanism preferably consistsof a bolt tip 38, which is preferably constructed out of delrin or metaland is connected to piston 32, housed in cylinder body 31. Piston 32 isalso constructed out of delrin or metal, and is connected to valve pin33, housed on the interior of piston 32. In the loading position, valvepin 33 is forced rearward and seal 70 (located on a rearward portion 33a of the valve pin 33) is pushed against the lip 75 of valve housing tip35, holding high-pressure compressed gas A on the rearward face 33 b ofvalve pin 33 and preventing the flow through bolt tip 38. All seals,including o-ring 70 are constructed out of urethane, BUNA, or TEFLON, orany other substance that effectively prevents gas leakage beyond thesurface of the seal. Valve housing tip 35 is integrally connected tovalve housing 34, which prevents leakage of high-pressure compressed gasaround the valve housing 34. Seals 102 also prevent leakage ofhigh-pressure gas and are placed at each connecting section of thevarious components. Cylinder 31 surrounds valve housing 34 and providessealed housing for piston 32, which contains a first surface 72 for lowpressure gas B to flow into to drive piston 32 rearward and seal valvepin 33 against tip 35. Valve housing 34 preferably contains an interiorchamber 36 for storing compressed gas to be used to fire a projectilefrom the gun.

The variable pneumatic sear 29 of the compressed gas gun of the presentinvention preferably consists of a control valve 30, a piston 32,residing in preferably sealed cylinder housing 31. Control valve 30directs low pressure compressed gas from low pressure regulator 21through manifold 41 to the cylinder housing 31, allowing gas to contactfirst surface of piston 32, driving the piston 32 rearward to seat thevalve pin 33 when de-actuated, which is considered the loading position.The low pressure compressed gas is able to drive the piston 32 rearwardagainst high-pressure gas pressure on valve pin 33 because the surfacearea of first surface 72 of piston 32 is larger than that of the surfaceof valve pin 33. Control valve 30 preferably consists of a normally openthree-way valve. When actuated, a normally open valve will close itsprimary port and exhaust gas from the primary port, thereby releasingpressure from the first surface of piston 32, through a port 42 drilledinto manifold 41. This allows high pressure compressed gas, pushingagainst the smaller surface area of valve in 33, to drive pin 33 forwardand break the seal by o-ring 70 to release the stored gas from valvehousing 34. Compressed gas then flows around valve pin 33, through portsin piston 32, and out through bolt tip 38 to launch a projectile fromthe barrel 10.

Control valve 30 is preferably controlled by an electrical signal sentfrom circuit board 63. The electronic control circuit consists of on/offswitch 87, power source 64, circuit board 63, and micro-switch 86. Whenthe gun is turned on by on/off switch 87, the electronic control circuitis enabled. For convenience, the on/off switch 87 (and an optionaladditional switches, such as that for adjacent anti-chop eye thatprevents the bolt's advance when a paintball 100 is not seated withinthe breech) is located on the rear of the marker, within a recess 88shielded on its sides by protective walls 89. This location protects theswitch 87 from inadvertent activation during play. The switch 87 ispreferably illuminated by LEDs.

When actuating switch 86 by manually depressing trigger 24, anelectrical signal is sent by circuit board 63 to the control valve 30 toactuate and close the primary port, thereby releasing valve pin 33 andlaunching a projectile. Once the momentary pulse to the control valve 30is stopped by circuit board 63, the electronic circuit is reset to waitfor another signal from switch 86 and the gun will load its nextprojectile. In this manner, the electrical control circuit controls afiring operation of the compressed gas gun.

A description of the gun's operation is now illustrated. The function ofthe pneumatic sear is best illustrated with reference to FIGS. 3 and 4,which depict the movements of piston 32 more clearly. Compressed gasenters the high-pressure regulator 50 through the input port 49. Thehigh-pressure regulator is generally known in the art and regulates thecompressed gas to about 200-300 p.s.i. These parameters may be changedand adjusted using adjustment screw 51. which is externally accessibleto a user for adjustment of the gas pressure in the high-pressureregulator. This high-pressure gas is used to actuate the firing valveand launch a projectile from the barrel 10 of the compressed gas gun.Upon passing through high-pressure regulator 50, compressed gas is fedboth through gas transport tube 7 to the valve chamber 36 via manifold8, and through port 5 to the low pressure regulator 21. Low-pressureregulator 21 is also generally known in the art. Compressed gas isregulated down to approximately between 50-125 p.s.i. by thelow-pressure regulator, and is also adjusted by an externally accessibleadjustment screw/cap 28, which is preferably externally manuallyadjustable for easy and quick adjustment. Compressed gas then passesthrough port 25 into manifold 41, where electro-pneumatic valve 30directs it into cylinder housing 31 through low pressure passages 74 andlow pressure gas pushes against first surface 72 on piston 32, drivingit rearwards and seating seal 70 against valve housing tip 35. Note thatpiston's 32 movement in the rearward direction is limited by contactbetween the second surface 76 and a stop 34 a on the valve housing 34.

This allows bolt tip 38 to clear the breech area of the body 3, in whichstage a projectile 100 moves from the feed tube 6 and rests directly infront of bolt tip 38. The projectile is now chambered and prepared forfiring from the breech. The high-pressure compressed gas, which haspassed into the valve chamber 36 via high pressure passage 37, is nowpushing against valve pin 33 on the rear of piston 32. The seal createdby o-ring 70 on valve pin 33 is not broken because the force of thelow-pressure gas on the first side of cylinder 31 is sufficient to holdthe valve pin 33 rearward.

When trigger 24 is depressed, electro-pneumatic valve 30 is actuated(preferably using a solenoid housed within the manifold 41, shutting offthe flow of low-pressure gas to housing 31 and venting the housing 31via manifold 41. This allows the higher pressure gas, which is alreadypushing against valve tip 33 from the rear, to drive valve tip 33forward to the firing position and break the seal 72 against the housing35. Bolt tip 38, which is connected to piston 32, pushes a projectileforward in the breech and seals the feed tube 6 from compressed gasduring the first stage of launch because the valve pin 33 is stillpassing through valve housing tip 35 during this stage. This preventsgas leakage up the tube 6 and positions the projectile for accuratelaunch. Once the valve pin 33 clears the housing tip 35, a flow passageD is opened, and the higher pressure gas flows through ports drilledthrough the interior of piston 32 and bolt tip 38 and propels thepaintball from barrel 10. Note that the piston's 32 movement in theforward direction is limited by contact between the first surface 72 anda shoulder 73 within the cylinder 31.

The signal sent to electro-pneumatic valve 30 is a momentary pulse, sowhen the pulse ceases, the valve 30 is de-actuated. This allowslow-pressure gas to enter cylinder housing 31 and drive valve piston 32rearwards against the force exerted by high-pressure gas to the seatedposition and allow loading of the next projectile.

Since piston 32 has a larger surface area on its outside diameter thanthe surface area on the valve pin 33, low-pressure gas is able to holdhigh-pressure gas within the valve chamber 36 during the loading cycleof the gun. This is more advantageous than a design where a separatepiston is used to actuate a separate valve, because the step ofactuating and de-actuating the piston is removed from the launch cycle.

In addition, the pressures of the low pressure gas and high pressure gasmay be varied according to user preference, thereby allowing for manyvariable pneumatic configurations of the gun and reducing problems witherratic cycling caused by using the same gas to control both the recockand launch functions of the gun. Because the mechanical sear iseliminated, the gun is also extremely lightweight and recoil issignificantly reduced. The gun is also significantly faster thanexisting designs because the independent piston operation is eliminated.

In an alternate embodiment, the compressed gas gun can operate at oneoperating pressure instead of having a high-pressure velocity circuitand a low-pressure recock circuit. This is easily accomplished byadjusting the ratio of the surface sizes of the first surface 72 and thevalve pin 33. In this manner, the size of the gun is reduced even morebecause low-pressure regulator 21 is no longer needed.

While the present invention is described as a variable pneumatic searfor a paintball gun, it will be readily apparent that the teachings ofthe present invention can also be applied to other fields of invention,including pneumatically operated projectile launching devices of othertypes. In addition, the gun may be modified to incorporate a mechanicalor pneumatic control circuit instead of an electronic control circuit,for instance a pulse valve or manually operated valve, or any othermeans of actuating the pneumatic sear.

It will be thus seen that the objects set forth above, and those madeapparent from the preceding description, are attained. It will also beapparent to those skilled in the art that changes may be made to theconstruction of the invention without departing from the spirit of it.It is intended, therefore, that the description and drawings beinterpreted as illustrative and that the following claims are to beinterpreted in keeping with the spirit of the invention, rather than thespecific details. set forth.

It is also to be understood that the following claims are intended tocover all the generic and specific features of the invention hereindescribed and all statements of the scope of the invention that, as amatter of language, might be said to fall therebetween.

1. A compressed gas driven gun comprising; a cylinder comprising apiston and a valve pin slidable coaxially therein; compressed gas at afirst pressure that biases the piston in a first direction; compressedgas at a second pressure that biases the piston in a second direction,and overcomes a force exerted by the first pressure biasing the pistonin the first direction so that the piston moves in the second direction;and a valve that, in response to a signal, decreases the second pressureenough to allow the compressed gas at a first pressure to bias thepiston in the first direction, which in turn releases the compressed gasat a first pressure to fire a projectile from the gun.
 2. The gun ofclaim 1 wherein the projectile is a frangible paintball.
 3. The gun ofclaim 1, further comprising: a source of compressed gas that suppliesboth compressed gas at the first pressure; and a regulator thatdecreases the first pressure to the second pressure.
 4. The gun of claim3, wherein the second pressure is adjustable.
 5. The gun of claim 3,wherein the regulator is adjustable by turning an externally accessibleadjustment cap.
 6. The gun of claim 1, wherein the valve decreases thesecond pressure by venting the compressed gas at a second pressure. 7.The gun of claim 1, wherein the compressed gas at a second pressure isvented through a manifold.
 8. The gun of claim 1, further comprising: atrigger that when depressed, sends the signal to the valve.
 9. The gunof claim 6, wherein the signal is pulsed in such a manner that once thecompressed gas at a high pressure is released, the valve ceasesdecreasing the second pressure.
 10. The marker of claim 1, wherein thefirst direction is a forward direction corresponding to a direction fromwhich the paintball exits the marker, and a rearward direction is adirection substantially opposite that of the forward direction.
 11. Thegun of claim 10, wherein the cylinder further comprises a valve housingtip fixed within a valve housing within the cylinder, that is sized toreceive a rearward portion of the valve pin when the compressed gas at asecond pressure biases the piston in the second direction, said rearwardportion having a face upon which the compressed gas at a first pressureacts to bias the piston in the forward direction.
 12. The gun of claim11, wherein the compressed gas at a second pressure acts on a firstsurface of the piston to bias the piston in the rearward direction. 13.The gun of claim 12, wherein when the compressed gas at the secondpressure acts to bias the piston in the forward direction, the piston'smovement in the forward direction is limited by contact between thefirst surface and a shoulder within the cylinder.
 14. The gun of claim12, wherein when the wherein when the compressed gas at the secondpressure acts to bias the piston in the rearward direction, the piston'smovement in the rearward direction is limited by contact between thesecond surface and a stop on the valve housing.
 15. The gun of claim 12,wherein when the compressed gas at the second pressure acts to bias thepiston in the forward direction, the piston's movement in the forwarddirection is limited by contact between the first surface and a shoulderwithin the cylinder; wherein when the wherein when the compressed gas atthe second pressure acts to bias the piston in the rearward direction,the piston's movement in the rearward direction is limited by contactbetween the second surface and a stop on the valve housing; and whereina surface area of the first surface is greater than a surface area ofthe face.
 16. The gun of claim 1, further comprising a power switch thatcontrols electricity driven functions within the gun including thesignal, said switch located within a recess within the gun.
 17. The gunof claim 16, wherein the recess is located in a rear portion of the gun,behind a trigger.
 18. The gun of claim 17, wherein the recess is locatedbelow the cylinder.
 19. The gun of claim 16, wherein the recess isdefines by at least two sidewalls located on either side of the switch.20. The gun of claim 16, further comprising a second switch locatedwithin the recess, for controlling other gun functions.
 21. The gun ofclaim 16, wherein the switch is illuminated.
 22. The gun of claim 21,wherein the switch is illuminated by an LED.
 23. A compressed gas drivengun comprising; a bolt slidable within a cylinder in a first directionunder a first pressure exerted by compressed gas, and slidable withinthe cylinder in a second direction under a second pressure exerted bythe compressed gas, wherein the first pressure acts on a first surfacearea smaller than that of a second surface area acted on by the secondpressure; and wherein when the bolt moves in one of the two directions,a paintball is driven from the gun by the compressed gas.
 24. Acompressed air driven gun comprising a power switch that controlselectricity driven functions within the gun including the signal, saidswitch located within a recess within the gun.
 25. The gun of claim 24,wherein the recess is located in a rear portion of the gun, behind atrigger.
 26. The gun of claim 25, wherein the recess is located belowthe cylinder.
 27. The gun of claim 24, wherein the recess is defines byat least two sidewalls located on either side of the switch.
 28. The gunof claim 24, further comprising a second switch located within therecess, for controlling other gun functions.